DESCRIPTION: (from the project Abstract) Shoulder pain is a common complication of hemiplegia occurring in 70-84% of stroke patients with a paralyzed upper extremity. A painful shoulder frequently results in decreased functional independence and poor motor recovery. Inferior subluxation of the glenohumeral joint is the major cause for the poststroke shoulder pain. Conventional intervention using slings often causes complications from immobilization. Recently, electrical stimulation of the shoulder muscles has been shown effective in reducing or preventing poststroke subluxation by a few pilot studies. Existing surface stimulation systems, however, can not be widely accepted because of poor muscle selectivity, accompanying pain and difficulty in daily application of the electrodes. We propose to use a percutaneous intramuscular stimulation approach to make the stimulation more effective, less painful and easier for daily use for several months. A miniature, programmable, multi-channel stimulator will be developed to drive a set of fine wire electrodes chronically indwelled inside the muscle belly. These electrodes are to be implemented by a hypodermic needle and can be easily withdrawn at the end of use. Preliminary clinical tests will be conducted to establish implantation procedure, stimulation protocol, and evaluation methodology. Feasibility of the project shall be determined by prototype device performance and initial medical outcomes.